NLO contributions to $B\to K{K}^{\ast }$ Decays in the pQCD approach

Abstract

We calculate the important next-to-leading-order (NLO) contributions to the $B\to K{K}^{\ast }$ decays from the vertex corrections, the quark loops, and the magnetic penguins in the perturbative QCD (pQCD) factorization approach. The pQCD predictions for the CP-averaged branching ratios are $Br(B^{+}\to K^{+}{\bar{K}}^{\ast 0})\approx 3.2\times 10^{-7}$, $Br(B^{+}\to {\bar{K}}^0{K}^{\ast +})\approx 2.1\times 10^{-7}$, $Br(B^0/\text{ov}{B}^0\to K^0{\bar{K}}^{\ast 0}+{\bar{K}}^0{K}^{\ast 0})\approx 8.5\times 10^{-7}$, $Br(B^0/\text{ov}{B}^0\to K^{+}{K}^{\ast -}+K^{-}{K}^{\ast +})\approx 1.3\times 10^{-7}$, which agree well with both the experimental upper limits and the predictions based on the QCD factorization approach. Furthermore, the CP-violating asymmetries of the considered decay modes are also evaluated. The NLO pQCD predictions for $\text{acp}(B^{+}\to K^{+}{\bar{K}}^{\ast 0})$ and $\text{acp}(B^{+}\to K^{\ast +}{\bar{K}}^0)$ are ${\text{acp}}^{dir}(K^{+}{\bar{K}}^{\ast 0})\approx -6.9$ and ${\text{acp}}^{dir}(K^{\ast +}{\bar{K}}^0)\approx 6.5$.

Comments: 29 pages,8 ps/eps figures, modified figures only